Process for producing fast colored resists under aniline black



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Patented June 24, 1930 UNITED STATES PATENT oer-ice.

WILLIAM COTTON, OF HOCHST-ON-THE-MAIN, GERMANY, ASSIGNOR T GENERAL ANI-LINE WORKS, INC., OF NEW YORK, N. Y., A CORPORATION OF DELAWARE PROCESSFOR PRODUCING FAST COLORED RESISTSUNIDER ANILINE BLACK No Drawing".Application filed January 28, 1926, Serial No. 84,510, and in GermanyFebruary 5, 1925.

Many attemptshave already been made to produce fast colored resistsunder aniline black by means of vat dyestufl's. However, such resistscould not be Widely adopted in practice because they are aptto formhalos. Now I have found that the above-mentioned draw-back can be easilyavoided by treating the goods with a padding bath such as is gencrallyused for dyeing with aniline black, printing on them enol esters of vatdyestuffs to which compounds giving an acid reaction on steaming Withouttendering the fiber are added, and then finishing the goods in themanner practiced in the production'of aniline black; It could not beforeseen that under the above stated conditions the enol esters can beoxidized more easily than aniline and that consequently they aresuitable for the production of colored resists under aniline black. L

The following example illustrates my invention:

Theprinting-color is prepared as followsz' 80 gr. of enol ester of 5-75' -7"-tetrabromined., vol. 1, page 300, No. 881) v 370 gr. of water 500gr. of neutral wheat-starch tragacanththickening '50 gr. of neutralammonium oxalate steamed-for 3 minutes, passed through a weak 1 bath ofpotassium bichromate, washed and Icla'imi'v. 1. Process for producingfast colored redigo, (Schultz, Farbstofl'tabellen, 6th,

out tendering the fiber and then finishing the goods in the mannerpracticed in the production of aniline black. .7

2. Process of producing i'ast colored reslsts under anllme black, whichcomprises printlng on goods, previously treated with a padding-bath asit is generally used in the finishing the goods in the manner practicedin the production of aniline black.

In testimony whereof, I affix my signa-' ture.

WILLIAM COTTON.

4o sists under aniline 'black, which consists in printing on the goods,previously treated with a paddin bath as it is generally used 'in thedyeing with aniline black, enol esters of vat dyestufl's to which areadded compounds which give an acid reaction on steaming wlth-

